摘要:

Epidemics of enterohemorrhagicEscherichia coliO157:H7 in the Pacific Northwest of the United States have highlighted the presence of colonic pathogens in the food chain. Risk factors for the disease and the properties of similarE. coliandShigellaare discussed, and advances in our understanding ofClostridium difficile-associated colitis and diarrhea,Campylobacter-induced dysentery, and illness due toEntamoeba histolyticaare presented. New insights into how bacteria survive stomach acidity and how they may be affected by breast milk, as well as modes of intracellular spread may provide the basis for new therapeutic modalities. The direct colonic damage HIV, itself, causes is discussed.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Viral infections of the gastrointestinal tract are a major worldwide cause of morbidity and mortality, especially in underdeveloped settings.Rotavirusis the leading cause of severe gastroenteritis in children and has been the object of intensive vaccine development efforts for several years. Although much has been learned, a satisfactory vaccine strategy has yet to be reported and many investigators are now testing alternative strategies. Recent advances in the study of gastroenteritis viruses include the cloning and characterization of the genomes of Norwalk-like viruses (now designated members of theCaliciviridae) and astroviruses, which have spawned a variety of epidemiologic studies and portend many more.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

During the past year, there have been important advances in the field of parasitic diseases of the gut. An immunodiagnostic test that allows the rapid identification of pathogenicEntamoeba histolyticahas been developed. Two new parasites that produce diarrhea have been characterized.Cyclospora, a cyanobacterium-like organism, is prevalent worldwide, affects immunocompetent individuals, and has been described as a cause of traveler's diarrhea.Encephalitozoonsp has been reported in patients with AIDS; however, unlikeEnterocytozoon bieneusi, it has the potential for systemic dissemination. Treatment ofTrichuris trichiurahas been demonstrated to rapidly correct the cognitive deficit present in children with trichuriasis. Lastly, combined treatment of hydatid disease by percutaneous drainage plus albendazole has been shown to be an effective form of management.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Gastrointestinal infections are common and important in infants and young children, particularly where poor hygiene and living conditions allow the spread of infectious agents. With increasing information about microorganisms that cause these infections and improved methods to detect them, many episodes that were once undiagnosed can now be attributed to previously unrecognized viruses, bacteria, and other pathogens. These advances facilitate better management and will permit more effective control and preventive strategies. This review highlights some recent reports about enterovirulent classes ofEscherichia coli, includingE. coliO157:H7, which causes the hemolytic-uremic syndrome and hemorrhagic colitis;Campylobacterspecies and a newCampylobacter-like organism (Arcobacter butzleri);Helicobacter pylori; Aeromonasspecies; and rotavirus. Important new information about intestinal parasites, includingGiardiaandCryptosporidium, has emerged that should prove of practical use in diagnosis and management in places where these parasites are prevalent in children, particularly in parts of the world where HIV infection has become established. A newly described organism, so far called coccidian-like or cyanobacterium-like body, has been found in patients with prolonged diarrhea (including travelers and expatriate residents) in several countries; the nameCyclospora cayetanensishas been proposed for this organism. This year's review concludes with a short commentary on some recent reports about risk factors that predispose children to gastrointestinal infections,eg, nutritional status, domestic hygiene, maternal hygiene behavior, and young children gathered in communal facilities like day care centers. Immune function status is also important, and deficiencies of single nutrients such as vitamin A, pyridoxine, folic acid, iron, and zinc may also play a role.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The most significant epidemiologic findings over this review period have been the isolation ofHelicobacter pylorifrom feces and the results of the Eurogast Study firmly linking colonization byH. pylorito the development of gastric carcinoma. With respect to the mechanisms of pathogenesis, the purification of the cytotoxin and an investigation of its mode of action are also important. Similarly, the demonstration of the effect ofH. pylorion somatostatin and gastrin-releasing peptide levels open further avenues of research. Numerous serologic tests are currently available, and an increasing use in screening procedures to reduce endoscopy workloads can be anticipated. The current regimen giving the highest eradication rate is bismuth, metronidazole, and tetracycline for 2 weeks, although the use of omeprazole with antibiotics is becoming more prevalent. Finally, the development of a vaccine is likely to be a major research area for the future.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Several new or reconfirmed strategies for the treatment of selected gastrointestinal infections have emerged from investigations published during 1992 and 1993. For traveler's diarrhea, fluoroquinolones are now preferred, except in Mexico where trimethoprim-sulfamethoxazole remains the antibiotic of choice. The efficacy of early treatment ofEscherichia coliO157:H7-associated hemorrhagic enteritis remains unproven. One dose of ciprofloxacin is sufficient to treat shigellosis caused by strains other thanShigella dysenteriaetype 1. Loperamide in combination with antibiotics shortens the clinical course of shigellosis. Treatment ofSalmonella-associated gastroenteritis with antibiotics prolongs carriage and is thus not recommended.Clostridium difficileasymptomatic carriage should not be treated with antibiotics. The treatment of cytomegalovirus colitis in HIV patients remains unclear; ganciclovir shows improvement only in histopathology in a controlled trial. A trial of paromomycin may be considered for HIV-positive patients with refractory cryptosporidiosis.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID